Conventionally, many studies have been made as to carbon dioxide separation apparatuses that separate carbon dioxide from a treatment-target gas containing carbon dioxide. Of these carbon dioxide separation apparatuses, there is a carbon dioxide separation apparatus that allows a treatment-target gas containing carbon dioxide to be brought into contact with a solid adsorbent loaded with amine or the like, such that carbon dioxide is selectively adsorbed (Patent Document 1). As to the adsorbent having adsorbed carbon dioxide, the adsorbed carbon dioxide is desorbed therefrom by a procedure in which the flow of the treatment-target gas is stopped, and thereafter the adsorbent is heated or decompressed. Thus, the adsorbent recovers its adsorption capacity and is regenerated. The regenerated adsorbent can be repetitively used for separating carbon dioxide by being brought into contact again with a treatment-target gas containing carbon dioxide.
In regenerating an adsorbent, the adsorbent is packed in a tower or the like. After the air remaining in the tower and gas other than carbon dioxide are exhausted (decompressed), the adsorbent is indirectly heated (the indirect heating scheme). Alternatively, steam is directly introduced into the packed bed of the adsorbent (the steam supply scheme, Patent Document 3). In the case where such adsorption of carbon dioxide and regeneration of the adsorbent are successively carried out, what is employed is the “fixed bed scheme” in which a plurality of adsorption towers are provided for alternately carrying out adsorption and desorption (Patent Document 2).